As you might guess, we have deep expertise on-hand for the Foundation as to MTB/MSB laws, and can confidently state we do not engage in MTB or MSB activity at the Bitcoin Foundation; we're just a member organization.
The state of California is blanket C&D-ing all Bitcoin businesses.
Given the online ads included in the letter, it appears they googled for "bitcoin" and used a screen grabber to copy/paste the law text. It's sad how messed up the CA gov't has gotten.
I wouldn't be surprised if the C&D were blanket. That said, when you Google for "Bitcoin Foundation" you see an "About" section in the #1 result (your website) which begins, "Our mission is to help people exchange...". I wouldn't put it past the state not to have read any further. ;-)
The state of California is blanket C&D-ing all Bitcoin businesses.